The University of Missouri-St. Louis Urban Information Center has recently updated this online application, which allows users to "generate a single 1990 'Basic Tables' (demographic profile) report for any of the supported geographic units, including census tract, block group, city (no size limit), 5-digit ZIP code, state, county or metro area for anywhere in the United States. Examples are...

Census data provides essential information that allows social scientists, economists, and historians to better understand and analyze the past and present. IPUMS (Integrated Public use Microdata Service) USA is a remarkable online database that allows anyone to explore and examine federal census data from 1850 through the present. Created by Steven Ruggles at the Minnesota Population Center, IPUMS...